Configuration API for PubNub POSIX C++ SDK

Posix C++ complete API reference for building real-time applications on PubNub, including basic usage and sample code.

Configuration

This documents the preprocessor definitions (macros) which are configuration options of C-core, which are kept in the pubnub_config.h header file. This header file is different for each platform. For some platforms, the definitions that "don't make sense" may be omitted from the header file.

Any definitions that you may find in pubnub_config.h, that are not listed here, should not be changed by the user.

PUBNUB_CTX_MAX: Maximum number of contexts

Maximum number of PubNub contexts that can be used at the same time. It is used only if the contexts are statically allocated. The default on hosted platforms (POSIX, Windows) is to use dynamically allocated contexts, so this is ignored. This is selected by linking in the "context allocation module" that you wish to use (static or dynamic).

A context is used to publish messages or subscribe to (get) them.

Each context can consume (for our purposes) a significant amount of memory, so don't put some number that is never going to be achieved here.

A typical configuration may consist of a single PubNub context for channel subscription and another PubNub context that will periodically publish messages about device status (with timeout lower than message generation frequency). This only needs two contexts.

Another typical setup may have a single subscription context and maintain a pool of contexts for each publish call triggered by an external event (for example, a button push). This would need N+1 contexts, N being the number of external events.

Of course, there is nothing wrong with having just one context, but you can't publish and subscribe at the same time on the same context. This isn't as bad as it sounds, but may be a source of headaches (lost messages, etc).

PUBNUB_BUF_MAXLEN: size of HTTP buffer

Size, in octets, of the HTTP buffer. This is a major component of the memory size of the whole Pubnub context, but it is also an upper bound on URL-encoded form of published message, so if you need to construct big messages, you may need to raise this. If you need to publish only messages of up to 2Kb size, you don't need more than, say 2500 PUBNUB_BUF_MAXLEN. But, if you need to publish messages larger than 2Kb size, you would need a bigger buffer.

It is designed to be "settable" from the compiler options, with the value in the header being the default. But, it's perfectly fine to not set it in the compiler options but change its ("default") value in here.

PUBNUB_DYNAMIC_REPLY_BUFFER: use dynamic reply buffer

Set to false (0) to use a static buffer and then set its size via PUBNUB_REPLY_MAXLEN. Set to true (anything !=0) to use a dynamic buffer, that is, dynamically try to allocate as much memory as needed for the buffer.

Default on hosted platforms (Windows, POSIX) is to use dynamic reply buffer. But, be warned, this can be a lot of data, megabytes, even. If you don't really have that much memory to spare, you may be better of with the static reply butt. OTOH, if the reply is too long for your statically allocated buffer, your transaction will, effectively, fail. This is a trade-off that is specific to your application.

PUBNUB_REPLY_MAXLEN: reply static length

This is only significant if PUBNUB_DYNAMIC_REPLY_BUFFER is true. In that case it defines the size, in octets, of the reply buffer. It will hold the whole (HTTP) body of the reply, not the (HTTP) headers.

Replies of API calls longer than this will be discarded and an error will be reported. Specifically, this may cause lost messages returned by subscribe if too many too large messages got queued on the PubNub server.

PUBNUB_ORIGIN: the DNS hostname of Pubnub

This is the string of the DNS hostname of the PubNub network. In general, you should not change this. Also, if thus configured (see PUBNUB_ORIGIN_SETTABLE), you can change the origin at runtime.

But, in the case that you do need to change it at compile time, but not at runtime and want to save some RAM in the context, it's OK to change this macro.

PUBNUB_ORIGIN_SETTABLE: is origin settable at runtime

If true (!=0), user will be able to change the origin at runtime. This incurs a small memory penalty, of keeping the runtime origin in the context. This is the default, as the "penalty" is small.

If false (==0), user will not be able to change the origin at runtime. Use this if you need to squeeze the RAM memory footprint of C-core.

PUBNUB_DEFAULT_TRANSACTION_TIMER: duration of transaction timeout

Duration of the transaction timeout set during context initialization, in milliseconds. Timeout duration in the context can be changed by the user after initialization (at runtime).

This is only used if timers support is used, which is the default on hosted platforms (POSIX, Windows).

PUBNUB_CALLBACK_THREAD_STACK_SIZE_KB: size of the PubNub thread

The size of the stack (in kilobytes) for the "polling" thread, when using the callback interface. We don't need much, so, if you want to conserve memory, you can try small values. It's hard to say what is the minimum, as it depends on the OS functions we call, but, you probably shouldn't try less than 64 KB.

Set to 0 to use the default stack size.

This is ignored when using the sync interface.

PUBNUB_PROXY_API: enable proxy support

Set to true (!=0) to enable the proxy support. This is the default on hosted platforms (Windows, POSIX). To actually use your proxy, you need to set proxy parameters (host, port, protocol) with the appropriate C-core APIs.

Set to false (==0) to disable the proxy support. This can provide for significant code savings, which may be important if you wish the cut down the code/flash footprint.

Keep in mind that, depending on how you build C-core, this may not be enough. That is, you might also need to not compile and link the proxy modules. This is illustrated in the sample makefiles.

PUBNUB_CRYPTO_API: enable automatic encryption/decryption

Set to true (!=0) to enable automatic encryption/decryption (publish, subscribe, message persistence) provided the pubnub_crypto_provider_t has been configured. Note that you must call the pubnub.set_crypto_module() function with the correct provider for your client to use the configured crypto module for automatic encryption/decryption. Otherwise, no encryption will be enabled.

Set to false (==0) to only return pubnub_crypto_provider_t but you will need to use it manually.

PUBNUB_MAX_PROXY_HOSTNAME_LENGTH: max length of proxy hostname

The maximum length (in characters) of the host name of the proxy that will be saved in the PubNub context. Set this according to your proxy (or your "possible future proxies"). It's one "proxy hostname" per context, so, don't put kilobytes here just in case, unless you know you can spare RAM.

PUBNUB_ONLY_PUBSUB: use only publish&subscribe

Set to true (!=0) to use only the Publish and Subscribe transactions. Set to false to use all the available Pubnub transactions - this is the default on hosted (POSIX, Windows) platforms.

This can provide for significant code size savings, if you don't need anything more than publish and subscribes, which may be important if you wish the cut down the code/flash footprint.

Keep in mind that this is not fully self contained. If you try to compile modules that are not needed when PUBNUB_ONLY_PUBSUB is true, you'll get a warning. If you actually link them, you will only save the code memory if your linker discards modules that are not used - in general, that is what linkers do, but it depends on your linker and the options you pass to it.

This is designed to be set via compiler options, with the value in the header file being the default. But, there is nothing wrong with setting it in the header itself.

Initialization

We recommend you use the Makefiles as a starting point in your own projects (whether they are based on Make or some other build tool / system or IDE).

The Makefile to build for POSIX C++ is available at posix.mk Please take a look at README for general info about the repo layout & contents.

Makefile with SSL/TLS Support

The Makefile for Posix C++ with SSL/TLS, (via OpenSSL) is available at posix_openssl.mk in the repo. See /openssl/README.md for info on how to build w/OpenSSL on POSIX C++ and other OpenSSL related data.

Including the Header

To include the PubNub POSIX C++ headers into your app, you must include pubnub.hpp:

#include "pubnub.hpp"
#include <iostream>

Once the header has been included, its easy to make calls to the PubNub service via the POSIX C++ API. The PubNub POSIX C++ API is flexible, supporting many different calling patterns. As such, before we dive in to actual coding samples, its important to go over the different types of calling patterns provided by the PubNub POSIX C++ client's futures support.

C++ Calling Patterns: Futures

pubnub::futres

The pubnub::futres class name is a portmanteau, blending C++ future with enum pubnub_res. It was purposely not named pubnub::future to avoid namespacing conflicts.

Both POSIX and Windows C++ SDKs use the pubnub::futres class, based on the std::future class (introduced in C++ 11) which provides a way to track the outcome of an operation asynchronously. Every operation that the SDK initiates with PubNub returns a futures object. This object allows to track the progress and completion of the operation via the status identifiers.

Using Futures Synchronously

There are several ways to use futures synchronously:

• Single await() or get()
• Separated start_await() and end_await()
• Your own last_result() loop

Single await() or get()

The pubnub::futres::await() method, similar to the pubnub_await() function from the C sync interface, is used to await the outcome of a transaction/operation. Since its function is the same as std::future<>::get(), we provide a synonym, and you can call pubnub::futres::get() with the same effect.

pubnub::context pb("demo", "demo");
pubnub::futres f = pb.publish("hello_world", "\"Here I am!\"");
if (PNR_OK == f.await()) {
    std::cout << "Published OK" << std::endl;
}
pubnub::futres f = pb.publish("hello_world", "\"Stuck in the middle\"");
if (PNR_OK == f.get()) {
    std::cout << "Published OK (again)" << std::endl;
}

Separated start_await() and end_await()

You don't have to await at once. You can start the await, and finish later. This is useful if you are working with more than one context, so you start an operation on one context, then start the await on that context, proceed to start an operation on another context and then end the started await.

pubnub::context pb("demo", "demo");
pubnub::context pbsub("demo", "demo");
pbsub.subscribe("hello_world").await();  // connect
pubnub::futres fsub = pbsub.subscribe("hello_world");
fsub.start_await();
pubnub::futres f = pb.publish("hello_world", "\"with you!\"");
if (PNR_OK == f.await()) {
    std::cout << "Published OK" << std::endl;
}
if (PNR_OK == fsub.end_await()) {
    std::cout << "Received messages:" << std::endl;
    for (auto &&msg : pbsub.get_all()) {
        std::cout << msg << std::endl;
    }
}

Your own last_result() loop

You don't have to use the await() functions. You can call last_result() in a loop and perform other operations. If you aren't doing other operations, this pattern won't be that useful for you -- in that case, just call await().

pubnub::context pb("demo", "demo");
pubnub::futres f = pb.publish("hello_world", "\"Waiting for Godot\"");
for (;;) {
    pubnub_res result = f.last_result();
    if (result() == PNR_STARTED) {
        // Do something while we wait
        play_some_tetris();
    }
    else if (PNR_OK == f.get()) {
        std::cout << "Published OK" << std::endl;
    }
}

Using Futures Asynchronously

All asynchronous logic is built upon pubnub::futres::then() (similar to what is available in some future libraries, and proposed for addition to C++17). There are several ways to use futures asynchronously:

• Using futures with a callback
• Using futures with a lambda
• Using futures with a function object

Using futures with a callback

By providing a free function or a static class method, you'll be using the C++ client similarly to that of the C callback interface.

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

static void on_publish(pubnub::context &pb, pubnub_res result)
{
    if (PNR_OK == result) {
          std::cout << "Published OK" << std::endl;
      }
}

int main(int argc, char *argv[])
{
    pubnub::context pb("demo", "demo");
    pubnub::futres f = pb.publish("hello_world", "\"Don't call us\"");
    f.then(on_publish);
    return 0;
}

Using futures with a lambda

Instead of a function, you can also pass a lambda to pubnub::futres::then:

pubnub::context pb("demo", "demo");
pubnub::futres f = pb.publish("hello_world", "\"Lambda\"");
f.then([=](pubnub::context &pb, pubnub_res result) {
    if (PNR_OK == result) {
        std::cout << "Published OK" << std::endl;
    }
    pubnub::futres f2 = pb.publish("hello_world", "\"the ultimate\"");
    f2.then([=](pubnub::context &pb, pubnub_res result) {
        if (PNR_OK == result) {
            std::cout << "Published OK (nested)" << std::endl;
        }
    });
});

Using futures with a function object

You can pass a callable object to pubnub::futres::then() - that is, an object of a class with an overloaded function call operator:

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

class bean_counter {
    int beans;
    public:
        bean_counter() : beans(0) {}
        void operator()(pubnub::context &pb, pubnub_res result) {
            if (PNR_OK == result) {
                ++beans;
            }
                  std::cout << "Published " << beans << " beans" << std::endl;
        }
};

int main(int argc, char *argv[])
{
    pubnub::context pb("demo", "demo");

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Since std::function<> is a generic function object, if you have one, just pass it to pubnub::futres::then:

void planet_express(std::function<void(pubnub::context&,pubnub_res)> parcel)
{
    pubnub::context pb("demo", "demo");
    pubnub::futres f = pb.publish("hello_world", "\"Deliver\"");
    f.then(parcel);
}

Memory Allocation

This client uses dynamic memory allocation for the PubNub contexts, but the usage is the same as for any other Pubnub C client - always use pubnub_alloc() to create a context (and check its return value) and always use pubnub_free() to dispose of a context.

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

#include "pubnub_alloc.h"
#include <stdio.h>
int main()
{
    pubnub_t *ctx = pubnub_alloc();
    if (NULL == ctx) {
        puts("Couldn't allocate a Pubnub context");
        return -1;
    }
    /* Do something with ctx...
        and then: */
    pubnub_free(ctx);
    return 0
}

Timers

We only provide one timer - the (total) transaction timer. In general, it is started when a transaction is started and stopped when a transaction is finished. If it expires, the transaction will be cancelled. Keep in mind that this canceling is local, so, for example, if you already published a message, but, for some reason, the HTTP response didn't arrive in time, this canceling will not revoke the publish - it will just stop the wait for response.

If the transaction timer expires, the outcome of the transaction will be timeout - different than when you cancel a transaction yourself.

The actual duration of the timer is at least as long as you set it. It could be significantly higher, depending on various platform issues. But, in general, it will be close to what you set.

You should set the timer after initializing the context and before starting a transaction. The duration you set will be used for all subsequent transactions, regardless of their type (that is for publish and subscribe and all other).

Thread safety

C-core supports thread-safe operation, though, for performance, you may think about not using it. To use thread-safety support, define the preprocessor symbol PUBNUB_THREADSAFE (just define it, the value does not matter).

Thread-safe Usage

Thread safety is internal. Just because you can access the PubNub context through the PubNub C-core SDK API from different threads safely, doesn't mean you're off the hook for your own data that is related to a context. For example, if you're using the callback interface and signalling an event from it to other (worker) thread(s), you have to synchronise that data transfer yourself.

If you compiled thread-safety support in, you are free to access the same context from different threads, pretty much in any way you wish. However, there are some advised guidelines you should follow:

• If you're using the sync blocking interface, threads that come to wait on the context may wait a long time, so try to avoid it (also, re-think your whole need for a thread-safe C-core)
• If you're using the sync non-blocking interface by calling pubnub_await, things are pretty much the same as for sync blocking interface
• If you're using the sync non-blocking interface and avoid pubnub_await, waiting threads will not block so long, but, pretty much the only useful thing you can do is cancel a transaction from another thread.
• Using the sync interface, it's perfectly fine to call pubnub_await or pubnub_last_result in different threads, but, you probably shouldn't do that, as it will make debugging harder.
• If you're using the callback interface, it's perfectly fine to call Functions from your callback, but, you should avoid doing that, except for some helper functions. Following this guideline will make your debugging, thus life, a lot easier

Thread-unsafe usage

If you compile without thread-safety support, obviously, you will have an SDK which is not thread safe - that is, it is not safe to use a single context from more than one thread at the same time. If you're using such SDK configuration in a multithreaded code, which, on POSIX, you likely are, then:

1. If at all possible, use a single context from only one thread - the one that created it
2. If 1. is not possible, provide some synchronization yourself, for example, using pthread condition variables, or just mutexes, or some higher abstraction, like message queues
3. As a special case, if you're using the callback interface, you can start a transaction in one thread and then don't touch the context from that thread any more - use it only in the callback. This is safe.

Threads and contexts

Keep in mind that it is perfectly safe to use different contexts from different threads at the same time. To each (thread) its own (context).

Keep in mind that it is perfectly safe to use different contexts from different threads at the same time. To each (thread) its own (context).

Transaction and Operation

The Posix C++ SDK operates as a set of transactions. A transaction is initiated by the client SDK and is defined as a single message exchange between the SDK and PubNub service. Every interaction that the client SDK initiates with PubNub is sequenced as a series of transactions which ultimately results in a PubNub service-specific operation.

Status and Events

The SDK provides a set of status and event identifiers which can help developers interact with the library. The status identifier codes are returned as part of the SDK's API invocation. These are used by the developer to check for status of transactions or for detecting normal / abnormal conditions in an API call. Some of the commonly used status codes are as follows

1. PNR_OK: Success, the transaction finished successfully
2. PNR_STARTED: The previously initiated transaction has started.
3. PNR_IN_PROGRESS: Indicates that the previous transaction with PubNub service is still in progress.

Refer to the API docs for a complete list of status identifiers supported by the library.

Events refer to the PubNub REST operations which are initiated by the client SDK. The most common example of events are subscribe and publish. A client subscribing for a channel is a subscribe event and a client publishing a message on a channel is a publish event.

Some of the common event identifiers are as follows:

1. PBTT_SUBSCRIBE: Subscriber operation
2. PBTT_PUBLISH: Publish operation

Refer to the API docs for a complete list of operations supported by the SDK.

Calling Patterns

This SDK provides sync and callback (notification) interfaces for retrieving the outcome of a Pubnub request/transaction/operation.

Sync

The sync interface works like this:

1. Start a transaction (say, publish - using pubnub_publish())
2. Either pubnub_await() the outcome, or use your own loop in which you check if (PNR_STARTED != pubnub_last_result())
3. Handle the outcome as you wish

This is illustrated in the Hello World example below (which is the same for any platform that supports sync interface).

Callback

The callback interface is somewhat more flexible, uses less CPU resources, but is, in general, a little harder to use. One way to use it is to emulate the sync interface:

1. Create a callback function (my_callback) per the prototype required by pubnub_register_callback()
2. In my_callback(), use a condition variable to signal that outcome was received
3. Set the callback via pubnub_register_callback()
4. Start a transaction (say, publish - using pubnub_publish())
5. Wait on the condition variable (the same one used in my_callback)
6. Handle the outcome as you wish

This is illustrated in the Hello World example below, using pthreads condition variable. Obviously, on platforms that don't support pthreads you will use some similar API (for example, SetEvent/WaitForSingleObject on Windows).

There are other ways to use the callback interface, like the state machine or similar, where the callback will handle the outcome of a transaction but will also start the next Pubnub transaction, or do other stuff that it needs to do. This is application specific, so we don't provide an example here.

Description

This function is used for initializing the PubNub Client API context. This function must be called before attempting to utilize any API functionality in order to establish account level credentials such as publish_key and subscribe_key.

Method(s)

To Initialize PubNub you can use the following method(s) in the Posix C++ SDK:

pubnub::context(std::string publish_key, std::string subscribe_key)

Parameter	Type	Required	Description
publish_key	std::string	Yes	Specifies the required publish_key to be used only when publishing messages to a channel. This key can not be specified if the client will not publish data to any channel, just use an empty string in this case.
subscribe_key	std::string	Yes	Specifies the required subscribe_key to be used for subscribing to a channel.

Basic Usage

Initialize the PubNub client API:

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("my_pubkey", "my_subkey");
std::string uuid("myUniqueUUID");
pn.set_uuid(uuid);
pn.set_ssl_options(pubnub::useSSL | pubnub::reduceSecurityOnError|pubnub::ignoreSecureConnectionRequirement);

Returns

It returns the PubNub instance for invoking PubNub APIs like publish(), subscribe(), history(), here_now(), etc.

Other Examples

Initialize the client

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("my_pubkey", "my_subkey");
std::string uuid("myUniqueUUID");
pn.set_uuid(uuid);

Initialization for a Read-Only client

In the case where a client will only read messages and never publish to a channel, you can simply omit the publish_key when initializing the client:

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("", "my_subkey");

Use a custom UUID

Set a custom UUID to identify your users.

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("myPublishKey", "mySubscribeKey");
pn.set_uuid("myUniqueUUID");

Initializing with SSL Enabled

This examples demonstrates how to enable PubNub Transport Layer Encryption with SSL. Just initialize the client with 1st set to true. The hard work is done, now the PubNub API takes care of the rest. Just subscribe and publish as usual and you are good to go.

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("my_pubkey", "my_subkey");
std::string uuid("myUniqueUUID");
pn.set_uuid(uuid);

pn.set_ssl_options(pubnub::useSSL | pubnub::reduceSecurityOnError|pubnub::ignoreSecureConnectionRequirement);

UUID

These functions are used to set/get a user ID on the fly.

Method(s)

To set/get UUID you can use the following method(s) in Posix C++ SDK:

Set UUID

set_uuid(std::string const &uuid)

Parameter	Type	Required	Description
uuid	std::string const &	Yes	UUID

Set random UUID

set_uuid_v4_random()

This is a utility function that is useful for creating random, unique user IDs on the fly.

Get UUID

uuid()

Basic Usage

Set UUID

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

std::string uuid("myUniqueUUID");
pn.set_uuid(uuid);

Get UUID:

std::cout << pn.uuid() << std::endl;

Returns

Get UUID returns the following output:

Type	Description
std::string const&	It's an empty string if UUID is not set.

Other Examples

Creating a function to subscribe to a channel with a unique name

pubnub::context pn("demo", "demo");
    struct Pubnub_UUID uuid;
    std::string channel_name;

    if (0 == pubnub_generate_uuid_v4_random(&uuid)) {
    channel_name = pubnub_uuid_to_string(&uuid).uuid;
    }

    pubnub_res res = pn.subscribe(channel_name).await();

    if (res != PNR_OK) {
    std::cout << "Failed to subscribe, error " << res << std::endl;
    } else {
    std::string msg = pn.get();
    std::string channel = pn.get_channel();

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Initializing with a custom uuid

Required UUID

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. If you don't set the UUID, you won't be able to connect to PubNub.

pubnub::context pn("myPublishKey", "mySubscribeKey");
struct Pubnub_UUID uuid;
std::string random_uuid;

if (0 == pubnub_generate_uuid_v4_random(&uuid)) {
    random_uuid = pubnub_uuid_to_string(&uuid).uuid;
    pn.set_uuid(random_uuid);
}

Creating a unique authKey for Access Manager on initialization

pubnub::context pn("demo", "demo");
struct Pubnub_UUID uuid;
std::string auth_key;

if (0 == pubnub_generate_uuid_v4_random(&uuid)) {
    auth_key = pubnub_uuid_to_string(&uuid).uuid;
    pn.set_auth(random_uuid);
}

Authentication Key

Setter and getter for users auth key.

Method(s)

set_auth (std::string const &auth)

Parameter	Type	Required	Description
auth_key	std::string const &	Yes	New auth key.

auth();

Basic Usage

Set Auth Key

pn.set_auth("my_new_authkey");

Get Auth Key

std::string auth_key = pn.auth();

Returns

Get Auth key returns the current authentication key.

Origin

Sets the origin to be used for the context. If setting of the origin is not enabled, this will fail. It may also fail if it detects an invalid origin. To reset to the default origin, pass an empty string.

Method

To set the origin for a Pubnub context use:

int set_origin(std::string const &origin)

Parameter	Type	Required	Description
Origin	std::string const&	Yes	The origin to use for the context. If empty, the default origin will be set

Basic Usage

To set the origin to the European data center explicitly:

pn.set_origin("ps.pndsn.com");

Returns

Type	Description
int	0: success, -1: fail

Set SSL Options

Sets the SSL options for a context.

Method(s)

void set_ssl_options(pubnub::ssl_opt opt);

Parameter	Type	Required	Description
opt	pubnub::ssl_opt	Yes	Specifies bitwise option: pubnub::useSSL pubnub::ignoreSecureConnectionRequirement

Basic Usage

pn.set_ssl_options(pubnub:useSSL | pubnub::ignoreSecureConnectionRequirement);

Returns

None

Crypto

These functions are used to configure the cryptography module used for encryption and decryption.

The crypto provider provides encrypt/decrypt functionality for messages. From the 4.15.0 release on, you can configure how the actual encryption/decryption algorithms work.

Each PubNub SDK is bundled with two ways of encryption: the legacy encryption with 128-bit cipher key entropy and the recommended 256-bit AES-CBC encryption. For more general information on how encryption works, refer to Message Encryption.

Legacy encryption with 128-bit cipher key entropy

You don't have to change your encryption configuration if you want to keep using the legacy encryption. If you want to use the recommended 256-bit AES-CBC encryption, you must explicitly set that in PubNub config.

Your client can decrypt content encrypted using either of the modules. This way, you can interact with historical messages or messages sent from older clients while encoding new messages using the more secure 256-bit AES-CBC cipher.

Older SDK versions

Apps built using the SDK versions lower than 4.15.0 will not be able to decrypt data encrypted using the 256-bit AES-CBC cipher. Make sure to update your clients or encrypt data using the legacy algorithm.

Method(s)

To configure the cryptography module use following method(s):

Configure local legacy module

auto legacy_crypto_module = pubnub::crypto_module::legacy(cipher_key);

Configure local AES CBC module

auto crypto_module = pubnub::crypto_module::aes_cbc(cipher_key);

Configure client legacy module

auto module = pubnub::crypto_module::legacy(cipher_key);
pb.set_crypto_module(module);

Configure client AES CBC module

auto module = pubnub::crypto_module::aes_cbc(cipher_key);
pb.set_crypto_module(module);

Basic usage

int main()
{
    try {
        std::string msg("Hello world from C++!");
        std::string cipher_key("enigma");

        std::vector<std::uint8_t> msg_vec(msg.begin(), msg.end());

        std::cout << "message to be encrypted: " << msg << std::endl;

        auto legacy_crypto_module = pubnub::crypto_module::legacy(cipher_key);
        auto legacy_encrypt_result = legacy_crypto_module.encrypt(msg_vec);

        std::cout << "legacy encrypted message: " 
            << std::string(legacy_encrypt_result.begin(), legacy_encrypt_result.end()) << std::endl;

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Configure AES CBC crypto module on the client for automatic encryption

// assuming the PUBNUB_CRYPTO_API is true
auto cipher_key = std::string("enigma");
auto module = pubnub::crypto_module::aes_cbc(cipher_key);
pb.set_crypto_module(module);